The disclosure relates generally to the direct cooling of electrical conductors in rotors of dynamoelectric machines. More particularly, the disclosure relates to a cooling manifold, which may be used alone or nested with other cooling manifolds, to directly cool such electrical conductors.
Dynamoelectric machines such as, e.g., generators, include a rotor having a plurality of axially extending slots disposed about the rotor circumference, into which the electrical conductors are inserted. In a direct cooled dynamoelectric machine, i.e., a dynamoelectic machine in which the machine is cooled directly by the atmosphere in which it operates, each slot may further include an axially extending subslot at a radially inward end of the slot for ventilation and cooling. The subslots are part of a ventilation scheme as known in the art, for transferring gas coolant axially along the rotor.
Radial cooling methods have been used for communicating cooling gas in a radially outward direction from the subslot through the conductors. However, radial flow cooling systems have typically only provided sufficient thermal performance for lower rated dynamoelectric machines. Diagonal flow cooling systems have been used in higher rated dynamoelectric machines due to their greater thermal performance, due in part to increased surface area. Diagonal flow cooling systems are, however, costly to implement.